1. Field of the Invention
The present invention relates to a method of removing an earphone noise and an apparatus thereof, and more particularly, to an apparatus and method of removing a noise generated by the power of microphone bias (MIC_Bias) of a portable terminal.
2. Description of the Related Art
A portable terminal provides various features such as a playing function of listening or watching an audio file or a video file that are previously stored, a camera function for photographing or taking a video, a digital broadcasting function for watching broadcast data transmitted from a broadcasting station, a wireless internet function for the usage of internet, and a message function for transmission of a short message or a multimedia message. Among these functions, an audio file playing function, in particular, is a function of playing various audio files that are prestored outputting the audio file through a speaker, and uses an earphone.
In operation, when a portable terminal uses a four-pole earphone, noise can be generated when detaching the four-pole earphone. In particular, noise can be generated while the L terminal or the R terminal of the four-pole earphone is in contact with the portable terminal when detaching the four-pole earphone from the interface unit. That is, the portable terminal turns the microphone (hereinafter “mike”) bias power off of the earphone from the point of when the four-pole earphone is not recognized. However, although the supply of the mike bias power is turned off, the mike bias power is not fully discharged within a time that the L terminal and the R terminal of the four-pole earphone are detached from the interface unit. Hence, the portable terminal recognizes that the L terminal and the R terminal of the four-pole earphone are still in contact with the mike terminal, so that it generates a noise.